RIR Sensor with ~3ft detection capability? Answered
Question for you sensor experts...
I'm looking to do a project that would involve detecting when an item passes through a doorway near ground level (~6 inches above ground level). Doing a bit of research it looks like a reflective infrared sensor would do the trick ... only issue I have come across is that there seem to be a slew of these sensors with detection capability of about 15mm max and then another class of these (home security grade) that have detection capability for several 10's of feet.
Any ideas on a RIR sensor (links appreciated!) that has capability ~2-3 feet? Another caveat is I'd like to string up multiple of these sensors in a close proximity, each with the sensor observing a 2-3 ft area right in front of it.